Thomas DICKENSON was likely the father of Nancy DICKENSON.
A Boyds marriage record identifies an Agnes PRESTON as marrying a Thomas DICKINSON in 1774 which fits with the christening records of his children. Furthermore, his daughter Nancy's second daughter was named Agnes which is good evidence in a family later known to have used a traditional approach to naming.
A possible 1841 census record gives his age as 70 (ie 70-74 years) and his profession as farmer. This profession fits with his daughter marrying a prominent farmer, but his age would not be right for marrying Agnes in 1774. The record has him living with Sarah FISHER b. abt 1804 and her family.
Accepting the marriage and ignoring the census record, Thomas would have been born about 1750 +/- 5 years.
It is possible that Thomas' father was the Myles DICKINSON who married Ann TOWNSON in 1746 as per the following marriage bond record:
"Lancashire, Westmorland: - Marriage Bonds, Deaneries of Lonsdale Kendal Furness and Copeland and Amounderness (Archdeaconry of Richmond), 1746-1755 Lancaster Marriage Bonds County: Westmorland
Dickinson, Myles, clerk & Ann Townson, both Broughton, Cartmel 01 May 1746"
Source: ancestry.co.uk
Further, Thomas' grandfather might have been the Thomas DICKINSON who acted as bondsman in the following marriage from the same source:
"Lancashire & Westmorland: - Marriage Bonds, Deaneries of Lonsdale Kendal Furness Copeland and Amounderness (Archdeaconry of Richmond), 1734-1738.
Lancaster Marriage Bonds. 1745-6 County: Westmorland
22 Jun 1736 John Ray, husb., of Cartmel and Hannah Hodgkinson of Broughton, p. Preston, wid. Bndsmn.: Thomas Dickinson, of Broughton in Preston, husb. At Preston p. church. Witn.: Jno. Sharpe."
The death registration : Sep 1837 - Dickinson Thomas Ulverstone 25 124 is not he right one.